The disclosure came on Monday at a time protests are holding across the country against increasing cases of rape and defilement of minors.
Vera Omozuwa, a 22-year-old student of the University of Benin, was reportedly raped and killed in an empty church in Benin City recently.
Eighteen-year-old Barakat Bello was also raped and machetted to death in Ibadan, Oyo State recently.
The development led to last week’s decision by the Federal Executive Council to go tough on culprits.
Speaking with State House correspondents at the Presidential Villa, Abuja on Monday, Adamu said out of the 717 cases, investigations have been concluded in 631 cases with the suspects already in court.
He said investigations were still ongoing in the remaining 52 cases.
The police boss further disclosed that 799 suspects were arrested in connection with the cases.
Adamu spoke after he joined the Minister of Information and Culture, Lai Mohammed; and the Minister of Women Affairs Development, Pauline Tallen; to meet the President Muhammadu Buhari.
He said: “It has come to the public knowledge now that because of the COVID-19 restrictions, we have a surge in cases of rape and gender-based violence.
“Law enforcement agents have been dealing with these cases, and in most cases, members of the public are not aware of the actions that the law enforcement agents have been taking.
“The Nigeria Police so far from January to May 2020 has recorded about 717 rape incidents that were reported across the country. About 799 suspects have been arrested, 631 cases conclusively investigated and charged to court and 52 cases are left and under investigation.
“The police, other security agencies, and other Non-Governmental Organisations have been collaborating to see to it that these cases of rape and gender-based violence are dealt with.”
He briefed reporters in company with the Minister of Women Affairs, Pauline Tallen, and the Minister of Information and Culture, Lai Mohammed.